The record is 10 minutes
http://www.mirror.co.uk/news/weird-news/the-fastest-sacking-in-football-history-476655
"Obviously, they thought I'd done a fantastic job after 10 minutes and let me go."
It's quite incredible the cast iron certainty some people speak with when discussing what's going on at the most chaotic club in the country with the most unpredictable and secretive owner around.
Who was that knacker doing it over the summer and changing his mind every few days? "The reason we aren't spending money is because of this Chinese takeover. You lot probably don't know as much as me about mergers and acquisitions but this is definitely what is happening behind the scenes as we speak". Fucking plank.